1. Field of the Invention
The present invention relates to a system status displaying device, and more particularly, to a device capable of reducing the number of light emitting diodes (LEDs) used for displaying a system status.
2. Description of the Related Art
The LED has found a multitude of roles in the field of opto-electronics, for example, indicators on hi-fi equipment, electronic telephone sets, cathode-ray tube phosphors, etc. LEDs are applied to various systems for their light emitting properties. In another example, LEDs are attached to a plurality of functional modules in a communication system housed in a cabinet so as to indicate the normal or abnormal function of the modules by giving off visible light.
Referring to FIG. 1, a prior art system is illustrated comprising a first module 10 and a second module 20. The first module 10 in the above system includes a first channel (CH1) 11 to a fourth channel (CH4) 14. Also, the second module 20 includes a first channel (CH1) 21 to a fourth channel (CH4) 24. The above system further comprises an LED controller 30 for sensing and displaying the states of each of channels of first and second modules 10 and 20. The LED controller 30 comprises LED 31-1 through 31-4 corresponding to the first channel (CH1) 11 through the fourth channel (CH4) 14 of the first module 10, and LED 32-1 through 31-4 of the first channel (CH1) 21 through the fourth channel (CH4) 24 of the second module 20.
According to FIG. 1, a conventional system is shown which includes a plurality of modules each of which comprises a plurality of channels having a system status displaying device with LEDs corresponding to each of the channels. A large number (modules.times.channels) of LEDs are required for a conventional communication system having a plurality of modules and channels. This is a drawback of the prior art system. A further disadvantage of the prior art system is that the size of printed circuit board (PCB) accommodating the LEDs becomes larger as the number of LEDs increases. Further, LEDs are typically continuously operated, even when not needed, resulting in unnecessary power consumption.